Given my aging Samsung Galaxy S6 averages about 30FPS for 20k bunnies in Firefox mobile, your criteria might actually be too lax...
Edit: And in Chrome on the same phone I'm in the mid 30's FPS for 50k bunnies.
To give an example: the Sony Xperia Z2 tablet appeared to be decent, because it had the - back then - state of the art Snapdragon 801 SoC.
I think I got less than 10k bunnies on it - no idea why(no power saving mode or anything), but it was a deal breaker for me.
Given my aging Samsung Galaxy S6 averages about 30FPS for 20k bunnies in Firefox mobile, your criteria might actually be too lax...
Edit: And in Chrome on the same phone I'm in the mid 30's FPS for 50k bunnies.